Adjustable flask bar and gagger combined



Feb. 27, 1934. E, F, OYSTER 1,948,867

ADJUSTABLE FLASK BAR AND GAGGER COMBINED Filed July 30, 1932 Z2 2/ I8 l6 7 .1

23' I9 a? it INVENTOR. c/r/ e7. Uy-sfer 26' BY ATTORNEYJ,

Patented Feb. 27, 1934 UNITED STATES PATENT OFFICE ADJUSTABLE FLASK BAR AND GAGGER COMBINED Earl F. Oyster, Shaker Heights, Ohio, assignor to The Osborn Manufacturing Company, Cleveland, Ohio, a corporation of Ohio Application July 30, 1932. Serial No. 626,523 10 Claims. (oi.22-111) gaggers and appurtenant parts heretofore used for this purpose.

In making sand molds for castings, it is necessary after the sand has been properly rammed or jolted around the pattern, to separate the cope from the pattern, thus leaving the sand in the cope unsupported except for the bridging of the sand across the flask. This problem does not, of course, arise in connection with the drag or bottom half of the flask in which the sand is always supported by the bottom boards on which the flask rests, but in the cope the sand cannot thus be supported by bottom boards and when the flask size exceeds a relatively small minimum over which the sand will bridge, it has been the practice to use bars and gaggers. These bars have commonly been made of wood or metal and disposed across the flask, holding the sand in place in the upper part of the flask but not serving to hold it in the lower surfaces of the mold adjacent the pattern.

In order to hold the sand in the lower part of the cope it has, therefore, been customary to make use of gaggers which are L-shaped pieces of cast iron or steel depending from the bars and more or less insecurely attached thereto by means of a liquid clay wash. This practice has never been very satisfactory and the problem of securely holding the sand together so that the separation of the pattern will be complete and clean with no dropped corners or pockets of sand which require patching has become more acute where mechanical jolting and squeezing of the mold has been adopted due to the fact that the gaggers employed interfere with the uniform flow and packing of the sand.

It is, accordingly, an object of the present invention to provide an apparatus which holds the sand securely in the cope in the stripping operation. Another object of the invention is to provide an apparatus all elements of which may be combined and used as a unit for this purpose. Still another object of the invention is to provide elements of an apparatus which may be interchanged and adjusted to accommodate a pattern of any contour. A further object of the invention is to provide elements for retaining the sand in a cope flask which elements do not interfere with the flowing and settling of the sand to a uniform density throughout the flask. To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawing and the following description set forth in detail certain mechanismembodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In said annexed drawing:

Fig. l is a top plan view of the upper half of a mold flask; Fig. 2 is a vertical section taken through the top half of a flask with a pattern in place; Fig. 3 is an enlarged vertical section taken along the line 33 of Fig. 2, showing a crab in elevation; Fig. 4 is a horizontal section taken along the line 44 of Fig. 3; and Fig. 5 is a vertical section taken along the line 5-5 of Fig. 3.

Referring to Fig. 1 of the drawing, the cope 6 is provided with a plurality of bars 7 usually extending across the width of the cope and attached to the side walls 8 thereof by means of bolts 9 passing through holes 11 in the side walls 8 and through holes in lateral flanges 12 provided on the bars '7. Nuts 13 are threaded on the bolts to maintain the cross bars in place. It will be noted that all of the holes 11 shown in the drawing are not in use for'supporting bars, these additional holes being provided liberally along the sides of the flask and closely spaced in order that the bars may be positioned wherever required to follow the contour of various patterns which may be present in the flask at one time or another.

Each of the bars 7 is pierced throughout its length by spaced holes 14 transverse to the length of the bar and, adjacent these transverse holes, the bar is also vertically pierced or grooved as at 15, there being a vertical groove or slot adjacent each transverse hole. Attention is directed at this point to the shape of the bars '7 in crosssection, as seen in Fig. 3 of the drawing, the section tapering toward both the top and bottom edges of the bar and the dimension of greatest thickness being located substantially nearer the top edge than the bottom edge. The reason for this conformation will be pointed out hereinafter. The transverse holes 14 pierce the bar at about its thickest dimension. Each of the recesses 15, which may lie wholly within the body of the bar but which preferably take the form of half-round grooves in one face of the bar, as shown in Fig. 4, is adapted to receive the shank 16 of a crab 17, the shank being circular in cross-section. These crabs are held in the grooves 15 and thus attached to the cross bars 7 by means of carriage bolts 18 which are placed in the transverse holes 14 and fastened by means of nuts 19. While other attaching means may be used, as will be obvious, bolts having the characteristics of car- I riage bolts are found to be particularly suitable since the large head 21 overlaps the groove or recess 15 and can thus be brought against the crab-shank 16 to hold the same securely in place by tightening the nut 19. In order to equalize the bearing of the bolt head 21 on the shank, a stud 22 is provided on the face of the bar '7 thus causing the head to rest on two diametrically opposite points, the stud 22 lying, if anything, a little below the outer surface of the shank. On the opposite surface of the bar a boss 23 is provided to strengthen the bar at the point where.

the nut 19 bears against it and to provide a bearing surface for this nut.

The crabs 17 depending from the cross-bars 7, as described above, carry on the end of the shank 16 a foot 24 which may be L-shaped or T-shaped as desired and which has a cross-section as indicated in Fig. 5, the same being roughly pearshaped with the maximum width substantially nearer the top edge of the foot than the bottom edge and tapering toward the top edge 25 and the bottom edge 26. This configuration is also provided in the cross-bar, as mentioned above, the cross-section of the bar sloping from the maximum width near the top edge toward the top edge 27 and the bottom edge 28. The purpose of this configuration is to offer as little obstruction to the flow of sand in the mold as possible during the mechanical jolting and squeezing op- 'erations which are now resorted to in place of hand-ramming in order to settle the sand around a pattern. The old form of gaggers was such as to interfere with the flowing of sand during this mechanical operation and required hand ran ming in order to prevent the formation of pockets in the mold where the sand had not been fully compacted. By making the bars and crabs of the contour described, the taper toward the lower edge facilitates the flow of the sand during jolting and the taper on the top edge facilitates the flow of the sand during the squeezing action of a molding machine. This desirable effect results from the minimum resistance to flow aiforded by a tapered section such as that described. However, the taper toward the edge 28 reduces the thickness of metal available to accommodate the grooves 15 at their lower ends and webs 28' are, accordingly, provided through which these grooves extend, thus prolonging the bearing surface for the shanks 16.

As mentioned, the foot 24 of the crab may be L-shaped or T-shaped to accommodate spaces of varying sizes and shapes in a pattern, in the outline of which shapes is is necessary to hold the sand when the cope is drawn. An L-shaped foot 29 and a T-shaped foot 31 are" shown in Fig. 2 of the drawing in connection with the problem presented by a pattern 32 of irregular contour. In addition to the adjustment which can be secured by thus altering the shape of the feet, this shape being susceptible of further alteration in addition to the shapes shown, as by making the two arms of the T of different lengths, and also being variable as to size, the shanks 16 h are freely adjustable both horizontally and vertically, so that the foot 24 can be raised or lowered according to the depth of a pattern at a given point and can be twisted radially about the axis of the shank to dispose the foot at any angle desired. For example, the individual crabs 33 are disposed with the feet perpendicular to the section taken in order to hold the sand in a depression of the pattern extending longitudinally in the flask, as well as extending laterally a distance corresponding to two of the recesses 15. Since the shanks 16 are cylindrical in form, they are freely rotatable in the half-round recesses 15 and slidable therein so that the feet 24 may be disposed at any desired angle and so that the crab as a whole may be raised or lowered in the flask to accommodate a shallower or deeper place in the pattern. When each crab has been adjusted in relation to the pattern, the bolts 18 may be inserted over the shank of the crab and the nuts 19 turned down so that the bolt-head 21 firmly engages the shank, holding the crab in the selected position. Thereafter, the projecting ends of the shanks may be struck off by a hammer, if made of brittle metal, so as to leave the projecting shank ends more or less flush with the top of the bars 7. The flask is then ready to receive the sand and to be subjected to the jolting. and squeezing operations used to prepare the mold.

It-will be noted that certain of the recesses 15, such as that indicated by the numeral 34, are not provided with crabs, the recesses 15 being provided in standard bars and the crabs then applied as indicated by the shape of the individual pattern, the crabs being omitted where the height of the pattern leaves only a small depth of sand below the bar not requiring the crabs for its retention. In addition, it has been pointed out that numerous sets of holes 11 are provided in the side wall of the cope sothat these bars, which may be. of standard dimensions for a given size of flask, can be inserted according to any spacing required by a given pattern. It will thus be seen that a special assembly of bars and gaggers is not necessary but that any required adjustment for various patterns may be secured by disposing the standard bars in the flask as required, by spacing crabs along these bars as needed, and by raising, lowering, and turning the crabs to accommodate the pattern as well as by selecting crabs with different shaped feet where necessary. These adjustable features make it possible to secure the necessary flexibility to accommodate various types of patterns without the necessity of providing a special shape of bar in which the bottom surface of the ,bar must follow the contour of the pattern in order to insure that no portion of the sand will drop upon lifting of the cope and also obviates the use of gaggers which, while providing the required flexibility, are uncertain in their effect. By the use of the herein described construction, the need of special flask bars either cast integral with the flasks or bolted in separately and specially formed to correspond with an individual pattern is avoided. This greatly reduces the expense involved since it is not necessary to provide an entirely new set of flasks or a new set of bars for each pattern encountered.

A further advantage of the present form of construction is that both the bars and the crabs are formed of a stream-line shape tapering toward their upper and lower edges, so that a minimum of interference with the flow of sand is set up. This feature is particularly important where mechanical methods, such as jolting and squeezing, are employed to settle the sand, in order to avoid the formation of pockets in the vicinity of the bars or crabs, which pockets would not be properly rammed bythese mechanical methods.

The present stream-line construction permits the sand to flow into all parts of the mold and to be firmly rammed in the vicinity of the bars and crabs. The operation of the herein described apparatus is very effective in performing its function of retaining the sand in the cope or upper half of the flask so that the cope lifts cleanly with no dropped corners or pockets of sand requiring subsequent packing and interfering with the obtaining of a maximum speed of molding with consequent minimum costs.

It will be realized that alterations maybe made in the structure described within the scope of the invention, it being possible to replace the described carriage bolts by other clamping means, such as with J bolts, and it may be found desirable, in some instances, to cast the bars integral with the flask.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention:

1. In a molding flask, a bar mounted on said flask, grooves in a face of said bar, a plurality of crabs adapted to depend from said bar and having shanks resting in said grooves, said crabs having narrow feet disposed at an angle to said shanks, different crabs having feet of different length, and clamping means on said bar securing said shanks in said grooves.

2. In a molding flask, a bar mounted on said flask, grooves in a face of said bar, crabs dependent from said bar and having shanks resting in said grooves, said crabs being vertically and horizontally adjustable with respect to the outline of a pattern in said flask, and clamping means on said bar securing said shanks in said grooves.

3. In a molding flask, a bar mounted in said flask, said bar having a cross-section tapering toward the top and bottom edges thereof, the

maximum width of said bar being substantially nearer the top than the bottom edge, a vertical groove in said bar and clamping means carried by said bar and adapted to cooperate with said groove to retain an element therein.

4. In a molding flask, a bar mounted in said flask, said bar having a cross-section tapering toward the top and bottom edges thereof, and means for supporting a crab from said bar.

5. In a molding flask, a bar mounted in said flask, said bar having a cross-section tapering toward the top and bottom edges thereof, the maximum width of said bar being substantially nearer the top than the bottom edge.

6. In a molding flask, a bar having a crosssection tapering toward the top and bottom edges thereof.

'7. In a molding flask, a bar having a crosssection tapering toward the top and bottom edges thereof, the maximum width of said bar being substantially nearer the top than the bottom edge, recesses in said bar adapted to receive a plurality of crabs, and clamping means on said bar adapted to cooperate with said recesses to retain said crabs therein.

8. In a molding flask, a crab having a shank, and a laterally extending foot on said shank, said foot having a cross section rounded on top and tapering toward the bottom edge thereof and of maximum Width substantially nearer the top than the bottom edge.

9. In a molding flask having a cross-bar mounted therein, grooves in said cross-bar and a crab-shank mounted in each of said grooves and resting partly above the surface of said crossbar, the combination which comprises a bolt disposed in said cross-bar transversely to each said crab-shank, a head on said bolt extending over said shank, a stud on the face of said bar supporting said bolt-head and equalizing the bearing of the same on said shank, and a nut on the opposite end of said bolt adapted to bear on the other face of said bar.

10. In a molding flask, means for retaining sand comprising a principal element secured to the I sides of the flask and having a cross section substantially stream-lined in the direction of movement of sand during packing and one or more secondary elements depending therefrom, said secondary elements including portions in planes parallel to said principal element, and of similarly stream-lined cross-section.

EARL F. OYSTER. 

